Golf club head and a method of manufacture

ABSTRACT

Disclosed is a metal golf club head with optimum macro- and micro-structures and properties and a method for manufacturing a metal golf club head. The method comprises forging precisely a metal billet at a temperature between 35-47% of the melting temperature into a net or near-net lower portion shape comprising a face portion, a hosel portion, and an integrated sole and wall portion. The forging process is preferably performed in at least two stages, with the top stage forging a pre-form shape approximately equal to 60-80% of the final shape. The second stage of the forging process results in the net or near-net shape with only localized conditioning by machining or grinding. A crown portion is manufactured by stamping or forging, and then welded to the lower portion to form the metal golf club head.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The invention relates generally to golf clubs and, more particularly, to a golf club head and a method of manufacturing a golf club head using net or near-net forging.

[0003] 2. Description of Related Art

[0004] In recent years, a great amount of attention has been given by golf club designers, engineers, and manufacturers towards increasing the relative size of golf club heads and, in the process, decreasing the wall thickness to keep the weight within acceptable parameters. Such oversized golf club heads increase the mass moment of inertia, enlarging the effective hitting area, commonly referred to as the “sweet spot,” and, therefore, are more forgiving on miss hits where the golf ball is not struck in the center of the clubface. Additionally, decreasing the thickness of the club head walls generally increases the energy transfer from the golf club to the golf ball, and, therefore, increases the overall distance produced.

[0005] The energy transfer from a golf club to a golf ball is generally governed by the United States Golf Association (USGA) for USGA-sanctioned events within the United States, Mexico and Canada. In 1998, the USGA adopted a test to measure the Coefficient of Restitution (COR) rating of golf clubs, and set a maximum COR rating of 0.830 (0.822 with a test margin for error of 0.008) for any club used in a USGA-sanctioned event, such as USGA tournaments, rounds of golf to be used in the calculation of a USGA handicap, and the like.

[0006] The governing body for all other countries, i.e., the Royal and Ancient Golf Club of Saint Andrews (R&A), will start to regulate the energy transfer from a golf club to a golf ball in the same manner prescribed by the USGA, but for elite professional competitions only, beginning in 2003. The R&A announced in August 2002 that R&A would test the COR rating for professional golfers only in elite competitions through 2008, and, therefore, a higher COR golf club could be used if desired in any event governed by the R&A other than in those elite competitions up until 2008 when all clubs will be regulated for all golfers.

[0007] Various manufacturing techniques have been attempted to achieve a golf club possessing the above features, i.e., increasing the size of the sweet spot and the energy transfer from the golf club to the golf ball. For example, U.S. Pat. No. 5,518,240 to Igarashi (“Igarashi”), entitled “Golf Wood Club Head Fabricating From Cast Head Sections,” discloses the use of investment cast titanium sections that are welded together. By using investment casting, however, it is difficult to precisely control the wall thickness to allow the creation of some golf club heads, particularly a large volume golf club head, without irregularities caused by the casting and finishing procedures.

[0008] Yet another example is U.S. Pat. No. 5,527,034 to Parente (“Parente”), entitled “Golf Club and Method of Manufacture,” discloses precision milling a forged alloy block. The forged alloy block is precision milled to the desired dimensions. Precision milling, however, is an expensive and time-consuming process.

[0009] Yet another example is U.S. Pat. No. 6,089,070 to Hancock (“Hancock”), entitled “Method of Manufacturing a Metal Wood Golf Club Head.” Hancock discloses a combination of forging at high temperature and machining. A metal billet is prepared, heated to 50%-70% of its melting temperature, and impression forged into approximately the desired design. The billet or other conventional forge-shape is then machined to attain the desired final form and weight. The preparation of the metal billet at the high required temperatures, and the machining processes for final forge form, however, are expensive, time-consuming, and possibly destructive to the optimum structure and properties of the products.

[0010] Therefore, there is a need for a larger golf club head and a method for manufacturing a larger golf club head having thin walls and face. Furthermore, there is an additional need for a method of manufacture using a net forging process that does not require machining to achieve the desired shape, and that operate at relatively low temperatures for optimum product structures and properties. This forging process can be applied to accurately vary wall thickness to provide different COR values for otherwise identically forged club heads.

SUMMARY

[0011] The present invention provides a precision-forged metal golf club head and a method for manufacturing a forged metal golf club head using temperatures in the range below 50% of the melting temperature of the material. The method comprises forging a metal billet into a net or near-net forged lower portion shape comprising a face portion, a hosel portion, and a wall portion. The wall thickness can precisely be varied by the forge-process to achieve different COR values. A crown portion is fabricated from plate/sheet stock and welded to the lower portion to form the metal golf club head.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following description taken in conjunction with the accompanying drawings, in which:

[0013]FIG. 1 illustrates a metal golf club head that embodies the present invention;

[0014]FIG. 2 illustrates the components, prior to assembly, of the metal golf club head that embodies the present invention;

[0015]FIG. 3 is a data flow diagram illustrating one embodiment of the present invention in which a metal golf club head is manufactured;

[0016]FIG. 4 illustrates the welding of the second portion to the lower portion in accordance with one embodiment of the present invention;

[0017]FIG. 5A illustrates a metal golf club head having a 10-degree loft manufactured in accordance with one embodiment of the present invention;

[0018]FIG. 5B illustrates the thicknesses of the face portion of a metal golf club head manufactured in accordance with the present invention;

[0019]FIG. 5C illustrates the thicknesses of the integrated sole and wall portion of a metal golf club head manufactured in accordance with the present invention; and

[0020]FIG. 5D illustrates the thicknesses of the crown portion of a metal golf club head manufactured in accordance with the present invention.

DETAILED DESCRIPTION

[0021] Referring to FIG. 1 of the drawings, the reference numeral 100 generally designates a golf club head embodying features of the present invention. The golf club head 100 may generally comprise a face portion 110, an integrated sole and wall portion 112, a crown portion 114, and a hosel portion 116. The golf club head 100 is shown in a finished state such that the crown portion 114 includes an optional alignment mark 120 and the face portion 110 includes optional grooves and/or punch marks 122. Preferably, the golf club head 100 in a finished state has been sanded, painted, and polished as desired.

[0022]FIG. 2 illustrates the golf club head 100 in an unfinished state, after manufacturing the components and prior to assembly. The golf club head 100 generally comprises a first portion 210 and a second portion 212. The first portion 210 comprises the face portion 110, the integrated sole and wall portion 112, and the hosel portion 116, and may be manufactured as a single piece as described below with reference to FIG. 4. The second portion 212 comprises the crown portion 114 manufactured in a similar manner as the first portion, but may be manufactured by any suitable, well-known process such as stamping, casting, forging, and/or the like. As shown, the second portion 212 includes three optional alignment tabs 216 that are used to aid in the welding process discussed below with reference to step 328 (FIG. 3). The alignment tabs 216 are positioned such that they allow the second portion 212 to be placed stably upon the first portion 210 in preparation of welding. Alternatively, more or less alignment tabs 216 may be used, and the alignment tabs 216 may be placed in alternative positions.

[0023]FIG. 3 is a flow chart depicting steps that may be performed in accordance with one embodiment of the present invention in manufacturing the golf club head 100, particularly the first portion 210. The process begins in step 310, wherein a metal, or metal alloy, billet is heated to below 50% (generally between 35-47%) of the melting temperature of the selected metal in degrees Celsius, i.e., the temperature that the metal transitions from a solid state to a liquid state. For example, if the melting temperature of the metal is 1680 degrees Celsius, then 45% of the melting temperature is 756 degrees Celsius. In an embodiment of this, the billet is heated to 45-47% and in yet another embodiment, the billet is heated to approximately 40-47% of the melting temperature.

[0024] Preferably, the metal billet comprises 1-inch diameter bar stock of a titanium alloy whose nominal composition by weight is approximately 10% V, 2% Fe, 3% Al, and the balance Ti, commonly referred to as 10-2-3 Beta or Near-Beta Titanium alloy. This titanium alloy is preferred because of the ability to forge the alloy as discussed below while retaining the high strength characteristics and the ability to provide a spring-like action without becoming deformed, brittle, and/or cracking after impact. Furthermore, this alloy may be readily solution heat treated and aged to achieve a high strength and hardness after forging; therefore, forging can be conducted at a lower hardness than the finished product, which facilitates the forging. Other Beta-Titanium alloys, however, may be used to achieve the desired effect. The weight of the billet should be controlled so it is equal to or just slightly greater than the final weight of the product, since with net forging, only a small degree of flashing waste can be expected.

[0025] In step 312, the metal billet, while at approximately 35-47%, more preferably between 40-47%, and most preferably between about 45-47% of the melting temperature, is placed in a top set of dies that bend the metal billet into an elbow shape.

[0026] In step 314, the metal billet, while at approximately 35-47%, more preferably between 40-47%, and most preferably between about 45-47% of the melting temperature of the material, is placed into a second set of dies that impression forges the metal billet into a pre-form shape. In the preferred embodiment, which utilizes a 10-2-3 Titanium alloy, the impression forging is performed utilizing a male and female die under a pressure of approximately 250-1250 tons, resulting in a pre-form shape that is approximately 60-80% of the net shape, i.e., approximately 60-80% of the final shape as depicted in FIG. 2, except localized areas.

[0027] In step 316, the metal billet in the pre-form shape is reheated to the same temperatures as discussed above with reference to steps 310 and 314, that is, approximately 35-47%, more preferably between 40-47%, and most preferably between about 45-47% of the melting temperature. In step 318, the metal billet is net forged to a net shape that is consistent with the final product prior to assembly. Near-net forging can also be used, but the degree of waste will be greater and minimal additional machining or chemical milling will be required to achieve the final size and shape. In step 320, any flashing (excess material) is removed from the metal billet, and the metal billet is allowed to air cool.

[0028] The foregoing forging steps may be conducted with a relatively slowly-acting hydraulic forge press, using a die having high-strength alloy, such as a nickel alloy or a molybdenum alloy, die. In a hydraulic forge, the material is squeezed to the desired shape by the force of a hydraulic piston. The rate of a hydraulic forge is relatively slow as compared with a mechanical, screw, hammer, or forge press, and it is possible to achieve the desired final shape with a great degree of precision.

[0029] Once the flashing is removed, the forged part will have the desired shape and face thickness profile of the base version of the final product. Thus, no additional machining step should be required to alter the shape or thickness of the forged part to make the base version of the final product. After forging, the forged golf head or portion thereof will desirably have refined macro- and micro-structures.

[0030] For hollow club heads, such as metal woods and hollow irons, the club head is desirably forged in at least two, and possibly more, pieces. The forgoing procedures are applicable to each of the pieces, with the exception of the pre-bending step, which need not be conducted for a piece of the club head having relatively consistent deformation across its entire surface, such as a crown piece of a metal wood not including a hosel. However, the bending step can be included for such a piece, if desired.

[0031] If it is desired to have different versions of the golf club head that vary to a limited degree in certain characteristics, such as COR, face thickness, weight or center of gravity, but are otherwise of substantially the same size and shape, this can be accomplished in accordance with an embodiment of the invention by accurately varying the forge-operational variables for the base version. Thus, for example, in step 322, the face portion 110 is optionally, through varying processing variables and resultant face-geometry, made thinner to achieve a higher COR golf club head.

[0032] This can also be accomplished in accordance with in an embodiment of the invention by machining or chemical milling of the desired portion of the forged part made for the base version. Thus, for example, in step 322, the face portion 110 is optionally further machined and/or chemical milled to thin it to achieve a higher COR golf club head.

[0033] Preferably, the metal billet is net forged, as described above with reference to steps 310-320, to result in the lowest desirable COR golf club head, that is, one with a thicker face. Higher COR golf club heads can then be achieved by precision net-forging the face portion to a thinner dimension, which generally results in a higher COR rating. This process allows for a single forging process that creates essentially identical golf club heads with differing COR ratings. Differing COR ratings obtained by utilizing the net-forging process allows the desired COR driver to be produced without the need for additional machining, but may increase the manufacturing costs associated with varying the operational variables in the presses.

[0034] For example, in the preferred embodiment, the lowest desirable COR golf club head may be a golf club head with approximately a 0.830 COR rating, or slightly lower, because that is the highest COR rating allowed by the USGA. Non-USGA conforming golf club heads with a higher COR rating, such as a golf club head with a COR rating of 0.85830-0.90, and the like, utilize the same process, except with the either the additional forge step that the face portion decreases the thickness or, alternately, the additional machining or chemical milling step to decrease the thickness of the face to the desired degree.

[0035] In step 324, the metal billet is locally machined, drilled, and/or the like, to bore through the hosel portion 116. This step can also be used to create any desired marks, such as grooves 122, an alignment mark 120, and/or the like, particularly those that may not be the same in all versions of the completed golf head.

[0036] In step 326, as discussed above, the second portion 212 is formed by either the same or a similar forging method as described above, or some other suitable method, such as stamping, casting and/or the like. Furthermore, the metal or metal alloy used to create the second portion 212 may, but need not be, a different composition than that used for the first portion 210. For example, in the preferred embodiment, the second portion 212 comprises a different Titanium alloy. For example, the second portion 212 can be made from a Titanium alloy whose composition by weight is approximately 6% Al, 4% V, and the balance Ti, commonly referred to as 6-4 Titanium alloy, while the first portion 210 comprises a 10-3-10-2-3 Titanium alloy. The second portion 212 can also be made from 3% Al and 2½ V alloy, or CP Titanium alloy. Additionally, the second portion 212 is preferably forged from a piece of plate stock, instead of the bar stock used for the first portion 210, to further reduce manufacturing costs.

[0037] In step 328, the metal billet from step 324, i.e., the first portion 210 (FIG. 2), and the second portion 212 (FIG. 2) from step 326 are welded together, preferably as described below with reference to FIG. 4. In step 330, the assembled product from step 328 is finished-out by sanding, painting, and/or polishing as desired.

[0038]FIG. 4 illustrates the preferred manner of welding the first portion 210 to the second portion 212 in accordance with one embodiment of the present invention. Preferably, the first portion 210 is welded to the second portion 212 along the perimeter of the second portion 212. Preferably, the second portion 210 is spot welded to the first portion at the location of the alignment tabs 216, and hands, clamps, fixturing devices, or the like, are then used to position and/or compress the first portion 210 and the second portion 212 into the final form while a continuous bead weld is placed along the joint of the first portion 210 and the second portion 212. Preferably, the second portion and the first portion are constructed such that the welding may be performed without any substantial compression, e.g., welded while being hand-held without any other clamp or fixturing device. Preferably, the weld is created using a 6-4 Titanium alloy welding rod.

[0039] Additionally, a weld angle of approximately 47-55 degrees, but preferably 50-52 degrees, relative to horizontal as the sole of the first portion is placed on a horizontal surface, is used in locations in which the first portion 210 is substantially thicker than the corresponding second portion 212, such as along the face portion 110, to prevent blow-outs (holes that are melted through the material that is to be welded) and breaks. Additionally, a weld angle of approximately 47-55 degrees provides a stronger bond that penetrates the face portion, providing additional support for the face portion when the ball is struck and allowing a thinner face portion to be used. A different weld angle, such as approximately 45 degrees, is preferred in locations in which the first portion 210 is approximately the same thickness as the second portion, such as along the joint between the integrated sole and wall portion 112 and the second portion 212. In an embodiment of the welding process, the weld is continuous, with a single bead.

[0040] In step 329, the club head may be solution heat treated and aged to increase its hardness. For 10-2-3 Titanium alloy, the solution heat treatment and aging should be performed at approximately 600-800° C. for approximately 0.125 to 4 hours for solution-treating and approximately 350-600° C. for approximately 0.50 to 16 hours for aging. Desirably, the solution heat treatment and aging is performed in an environment substantially free of oxygen, such as in a vacuum or in an inert gas environment, such as argon. The solution heat treatment is preferably performed after the welding step and before final sanding and polishing. However, if desired for a particular material, the solution heat treatment and aging can be conducted prior to welding the pieces together.

[0041]FIGS. 5A to 5D illustrate an example of a golf club head, namely a 10-degree driver, manufactured according to the process described above, and is provided for illustrative purposes only and should not limit the present invention in any manner. Accordingly, the thicknesses may be altered as desired by the golf club designer to obtain the desired weighting characteristics without departing from the spirit of the present invention. The thicknesses of the various portions and the loft angle for a head having a desired loft angle are preferably determined by the third set of dies using net forging as described above, without the need for additional machining. However, as described above, limited variations in loft angle and face thickness, such as those desired for different versions of the base club head, can be achieved by varying the forging operations or by machining or chemical milling, as described above.

[0042] FIGS. 5A-5D illustrate a 10-degree driver head, the thicknesses of the face portion, the thicknesses of the sole portion, and the thicknesses of the crown portion, respectively, manufactured in accordance with the present invention. Preferably, the face portion has a height of approximately 1.95″, a length of approximately 3.7″, a roll having a radius of approximately 12″, and a bulge having a radius of approximately 12″. The center of the hosel portion preferably extends to a height of approximately 2.75″ from the bottom of the sole portion, and intersects the plane of the crown portion at approximately 0.55″ from the heel. As specified, the total weight of the 10-degree driver head is approximately 202 grams (192 grams of metal weight plus 10 grams of weighting material). Preferably, the forging process described above allows for a thin, light body to be produced. As a result, weighting material, such as glue and the like, may be added as is known in the art to further modify the center-of-gravity as desired.

[0043] As will be appreciated by one skilled in the art, the thicknesses of the sole portion may differ between the head designs. By altering the thicknesses of the respective sole portions as illustrated and described, the center of gravity is moved away from the face portion and towards the heel of the golf club head. Altering the center of gravity in this manner allows the golfer to close the clubface more easily and may be beneficial to some golfers, such as golfers with a high handicap.

[0044] It is understood that the present invention can take many forms and embodiments. Accordingly, several variations may be made in the foregoing without departing from the spirit or the scope of the invention. For example, the multi-piece construction may consist of other elements of the club head, such as one piece incorporating the face, crown, and hosel and a second piece incorporating the sole and walls, and the like. Alternately, the multi-piece construction may consist of other elements of the club head, such as one piece incorporating the face, walls and hosel, another piece having the crown, and a third piece incorporating the sole. Other combinations are also possible.

[0045] Having thus described the present invention by reference to certain of its preferred embodiments, it is noted that the embodiments disclosed are illustrative rather than limiting in nature and that a wide range of variations, modifications, changes, and substitutions are contemplated in the foregoing disclosure and, in some instances, some features of the present invention may be employed without a corresponding use of the other features. Many such variations and modifications may be considered obvious and desirable by those skilled in the art based upon a review of the foregoing description of preferred embodiments. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the invention. 

1. A method of manufacturing a metal golf club head, the method comprising the steps of: forging a first portion of the club head including a face portion at a temperature of between 35-47% of the melting temperature of the material in degrees Celsius; and fabricating a second portion including a crown portion.
 2. The method of claim 1, wherein the first portion comprises a face portion, a hosel portion, and an integrated sole and wall portion.
 3. The method of claim 1, wherein the first portion comprises a face portion, a hosel portion, and an integrated sole and wall portion, and wherein the weld angle between the second portion and the face portion is 47-55 degrees relative to horizontal, and wherein the weld angle between the second portion and the hosel portion and the integrated sole and wall portion is approximately 45 degrees relative to horizontal.
 4. The method of claim 1, further comprising the step of milling the face portion to obtain a thinner face portion.
 5. The method of claim 1, wherein the first portion is forged from 10-2-3 Titanium alloy.
 6. The method of claim 1, wherein the second portion is a different Titanium alloy.
 7. The method of claim 1, wherein the step of forging the first portion further comprises the steps of: heating a first metal billet to approximately 35-47% of the melting temperature of the metal; forging the first metal billet into a first pre-form shape; heating the first pre-form shape to approximately 35-47% of the melting temperature of the metal; and forging the first pre-form shape into a first net or near-net shape of the first portion.
 8. The method of claim 1, wherein the step of forging a first portion further comprises the step of: prior to forging the first metal billet into a first pre-form shape, bending the first metal billet into an elbow shape.
 9. The method of claim 1, wherein the step of welding is performed without substantial compression.
 10. The method of claim 8, further comprising heating the metal billet to approximately 35-40% of the melting temperature of the metal prior to bending.
 11. The method of claim 1, wherein the welding is performed by welding the second portion to the first portion at a weld angle of 47-55 degrees relative to horizontal along the face portion, and at a weld angle of approximately 45 degrees relative to horizontal along the integrated sole and wall section.
 12. A method of manufacturing a portion of a metal golf club head, the method comprising the steps of: forging a first metal billet heated to approximately 35-47% of the melting temperature of the metal; performing the above step at least two times until a net or near-net shape of a first portion is formed from the first metal billet; forging a second metal billet heated to approximately 35-47% of the melting temperature of the metal until a net or near-net shape of a second portion is formed from the second metal; and welding the first portion and second portion together.
 13. The method of claim 12, wherein the first metal billet and the second metal billet are composed of different alloys.
 14. The method of claim 12, further comprising welding the second portion to the first portion at a weld angle of 47-55 degrees relative to horizontal.
 15. The method of claim 12, wherein the first portion comprises a face portion, a hosel portion, and an integrated sole and wall portion, and wherein the second portion comprises a crown portion.
 16. The method of claim 12, wherein the first portion comprises a face portion, a hosel portion, and an integrated sole and wall portion, wherein the weld angle between the second portion and the face portion is 47-55 degrees relative to horizontal, and wherein the weld angle between the second portion and the hosel portion and the integrated sole and wall portion is approximately 45 degrees relative to horizontal.
 17. The method of claim 12, further comprising the step of milling the face portion to obtain a thinner face portion.
 18. The method of claim 12, wherein the first portion is forged from 10-2-3 Beta Titanium alloy.
 19. The method of claim 12, wherein the second portion is forged from a different Titanium alloy.
 20. A method of manufacturing a metal golf club head, the method comprising the steps of: heating a first metal billet to approximately 35-47% of the melting temperature of the metal; forging the first metal billet into a first pre-form shape; heating the first pre-form shape to approximately 35-47% of the melting temperature of the metal; forging the first pre-form shape into a first net or near-net shape of a first portion having a face portion, a hosel portion, and an integrated sole and wall portion; fabricating a second portion having at least a crown portion; placing the first portion on a horizontal plane; and welding the second portion to the first portion at a weld angle of 47-55 degrees relative to horizontal along the face portion, and at a weld angle of approximately 45 degrees relative to horizontal along the integrated sole and wall section.
 21. The method of claim 20, wherein the metal golf club head is a metal wood golf club head with a loft angle from 8-24 degrees.
 22. The method of claim 20, wherein the second portion is fabricated by forging a second metal billet heated to approximately 40-47% of the melting temperature of the metal.
 23. The method of claim 20, wherein the first metal billet comprises a 10-2-3 Beta Titanium alloy.
 24. The method of claim 20, wherein the second portion comprises a different Titanium alloy.
 25. A method of manufacturing a metal golf club head, comprising the steps of: heating a first metal billet to 35-47% of the melting temperature of the metal; forging the first metal billet into a first pre-form shape; heating the pre-form shape to 35-47% of the melting temperature of the metal; forging the pre-form shape into a net or near-net shape substantially equivalent to a lower portion of a base golf club head, the lower portion comprising a face portion, an integrated sole and wall portion, and a hosel portion; fabricating a second portion having at least a crown portion; and welding the crown portion to the lower portion.
 26. The method of claim 25, wherein the first metal billet comprises a 10-2-3 Titanium alloy and the second portion comprises a different Titanium alloy.
 27. The method of claim 20, wherein the step of welding utilizes a 6-4 Titanium alloy welding rod.
 28. The method of claim 20, wherein the step of welding is performed at approximately a 50-52 degree angle relative to horizontal along the face portion.
 29. A metal golf club head, comprising: a forged first portion that comprises net or near-net-forged material having, at a forge temperature, a refined macro- and micro microstructure and a second portion welded to the forged first portion.
 30. The apparatus of claim 29, wherein the weld is approximately 47-55 degrees relative to horizontal.
 31. The apparatus of claim 29, wherein the first portion comprises a face portion, a hosel portion, and an integrated sole and wall portion.
 32. The apparatus of claim 29, wherein the forged first portion and the second portion are composed of different alloys.
 33. The apparatus of claim 29, wherein the first portion is welded to the second portion at a weld angle of 47-55 degrees relative to horizontal.
 34. The apparatus of claim 29, wherein the first portion comprises a face portion, a hosel portion, and an integrated sole and wall portion, and wherein the second portion comprises a crown portion.
 35. The method of claim 29, wherein the first portion comprises a face portion, a hosel portion, and an integrated sole and wall portion, wherein the weld angle between the second portion and the face portion is 47-55 degrees relative to horizontal, and wherein the weld angle between the second portion and the hosel portion and the integrated sole and wall portion is approximately 45 degrees relative to horizontal.
 36. The apparatus of claim 29, further comprising the step of milling the face portion to obtain a thinner face portion.
 37. The apparatus of claim 29, wherein the first portion is forged from 10-2-3 Beta Titanium alloy.
 38. The apparatus of claim 29, wherein the second portion is forged from a different Titanium alloy.
 39. The apparatus of claim 29, wherein the first and second portions have been solution heat treated.
 40. The method of claim 1, further comprising the step of solution heat treating the golf club head. 